Gemstone setting



FIG. 1 is a perspective view of a gemstone setting showing my new design;

FIG. 2 is a front side view thereof, the rear side, left side and right side views being identical thereto;

FIG. 3 is a top view thereof; and,

FIG. 4 is a bottom view thereof.

The broken lines shown in the drawings illustrate portions of the gemstone setting that form no part of the claimed design. 

CLAIM The ornamental design for a gemstone setting, as shown and described. 